Adjustable brake transmission unit



March 14, 1939. M. T. VOIGT ADJUSTABLE BRAKE TRANSMISSION UNIT Filed March 13, 1936 A773 A/EX Patented Mar. 14 1939 UNITED STATES PATENT: circles I 2,150,867 I ADJUSTABLE BRAKE TRANSMISSION UNIT Max T. Voigt, Reading, Pa., assignor to American Safety Table Company, Inc., Reading, Pa., a corporation of Pennsylvania -Applicatio'n March 13, 1936, Serial mrsasas 2 Claims.

, My invention relates to transmission units, particularly those useful in connection with sewingmachines. My invention is illustrated in connection with a transmission unit'of individual drive type but is useful in transmission units of the in the path of the treadle or other operating dei5 -vice at which the brake becomes operative, thereby rendering constant care on the part of the operator necessary to locate the exact point at which the needle of the sewing-machine will be stopped. This is an undesirable strain and imp ses the necessity of skill on the part of the operator. My invention includes the provision of means for adjusting the brake-shoe to take up the wear so that the point in the path of travel of the treadle or other operating member at which the brake becomes operative remains the I same, thereby enabling the operator to stop the sewing-machine needle at the samepoint and with greater accuracy. Y

More specifically, my invention comprises av transmission unit having a brake-shoe adjustabiy mounted on a stationary part of the transmission unit and having readily detached means for lookme said brake-shoe in each of its adjusted posi- I tions.

For a further exposition of my invention, reference is made to the annexed drawing and specification at the end whereof the novel features of my invention will be pointed out and claimed.

' In the drawing: Fig. 1 is a side elevation of my device, with the parts shown in vertical cross-section.

Fig. 2 is an end view, with parts broken away in transverse cross-section.

In that embodiment of my invention chosen from amongst others for illustration in the draw-- ing and description in the specification, my device is shown as being suitable for attachment to a table I or other device by means of a bracket 2 or other support which forms a part of a drum or si..1ilar element 3 forming a part of the housing. To one-end of drum 3 is mounted a motor 4, shown as an electric motor but which may be of any convenient type. Motor 4 has a shaft 5 to which is attached a clutch-driving member 6.

The opposite end of drum 3 from that on which motor 4 is mounted bears an end plate I having an opening in which is slidably mounted a sleeve 8, which provides a slidable bearing for driven clutch member 9 which is mounted on shaft II, to which is also attached a pulley II by means of 5 which the sewing-machine or like device is driven. Sleeve 8 bears screws I! or like devices thereo bymeans-of which yoke I3 is connected to ar lland thence to link II which is connected to foot-treadleor similar operating device. 10

On end plate I is mounted a support Ii whic conveniently takes the form of an annular ring having engagement with end plate 1 by means of screw-threads IT. Support It carries brake-shoe l8 on its face opposite clutch-driven member 9.

In its rear, support it carries a plurality of bores I 9. End plate -I carries a locking-screw which has screw-threaded engagement therewith. Locking-nut 2| retains locking-screw. 20 in position. The end of locking-screw 2i enters .into one of the bores I! in support It and thereby retains 'the'support I! and consequently brakeshoe it in position. v t

The operation of my device is as follows: when it is desired to adjust the position of brake-shoe It to take up for wear, locking-nut 2| is loosened and locking-screw "is backed ofl so that it clears the bore l8 which it previously occupied. Support it is then rotated on screw-threads ll until 30 another bore is aligned with the end of lockingscrew Ili. Locking-screw 20 is then screwed forward so that its end enters. the bore l9 and locks it inits adjusted position. Locking-nut 2| is then screwed up to retain locking-screw 2| in 35 position.

I do not intend to be limited save as the scope of the prior art and of the attached claims may require. V, x I claim: 4

1. In a transmission unit, a stationary member having screw-threads thereon, an annular sup port having screw-threads for co-operation with said screw-threads on said stationary member, a brake-shoe carried by said support, said sup- 45 port being provided with a plurality of bores arranged in a ring and facing said stationary member, said stationary member being provided with a screw-threaded hole therethrough located so that each of said bores in said support may be 50 aligned therewith by rotating said support, and a locking-screw co-operating with said. screwthreaded hole in-said stationary member and having an end adapted to enter one of said bores in said support and to therebyflock said support against movement relative to said stationary member.

2. In a transmission unit, the combination of, a housing having end plates, a clutch element mounted in one of said end plates for rotary and translatory movement relative thereto, a brake element mounted on said housing adjacent said clutch element so as to engage said clutch element at one end or its translatory movement, ad-

justing means provided between said end plate carrying said clutch member and said brake element, and locking means separate from said adjusting means provided between said end plate and said brake element to lock said brake element in various adjusted positions, said end plate having. openings therein which expose said brake element for adjustment. 

